Dissection instruments have found ample usage as manual surgical instruments in multiple surgical fields including abdominal surgery, orthopedics and neurosurgery. Their action is to mechanically dissect tissues. Dissectors assist in the detachment of normal tissues to enable appropriate penetration through the soft tissue layers or in the detachment of various pathological tissues from healthy tissues.
The detachment of tissues using standard mechanical tissue dissectors can be quite tedious and is often responsible for long surgical operations. In addition, post-operative complications may occur in some surgical procedures such as impairing the function of the remaining tissues, nerves or veins, hemorrhage, infections and recurrence. These complications result from the difficulties that surgeons may encounter in highlighting the cleavage planes, detaching tissue layers and obtaining hemostasis. An important technical progress in this field would be to facilitate the detachment of tissues, increase the success rate of cyst or tumor removals, avoid damage of remaining surrounding organs, reduce blood loss and post-operative adhesions, thereby reducing operation duration, reduce medical costs of such operations as well as health risks for patients.
It is known that when applied at the cleavage plane, sodium-2-mercaptoethane sulfonate or Mesna breaks the molecular bonds between tissue layers, thereby facilitating tissue separation. Specifically, Mesna breaks disulfide bonds of polypeptide chains and proteins. However, nowadays for tissue separation, Mesna is only available in liquid form. A major drawback of Mesna solutions is their instability as mentioned in U.S. Pat. No. 5,728,738. The liquid form is highly prone to oxidation and is therefore highly unstable especially in presence of metals. Therefore, it is common to store Mesna solutions in low iron glass containers under nitrogen blanket with stabilizers and anti-oxidants. When being used, the practitioner has to transfer the solution from glass containers to a delivery device or to a tube in order to bring the solution in contact with the desired tissue. This step increases contamination risk at the dissection site and increases surgery time. This is in addition to the high chances of oxidation of the stored Mesna solution thereby having a reduced Mesna activity when used for assisting surgery.
Other drawback of the Mesna in liquid form which is available today resides in the absence of concentration choice. In some procedures, larger quantities and/or different concentration of Mesna, from that readily available in commercial glass vials, are needed Indeed the practitioner can only dilute the Mesna which is available in liquid form and cannot use higher Mesna concentrations if required. This makes making the use of said vials tedious or inadequate. As mentioned in U.S. Pat. No. 5,728,738, Mesna solutions available are stabilized by addition of pH adjustment agents, additives such antioxidants and stabilizing agents thereby avoiding oxidation and/or the degradation of Mesna when the Mesna solution is stored. Addition of such agents presents a considerable risk for patient's health and increases the cost of said Mesna solutions. In addition, commercial solutions are not isotonic and may damage exposed cells when applied topically.
One of the objectives of the invention is to overcome at least part of the above mentioned problems. The invention aims at providing a device and method for increasing the shelf life of Mesna before use, optimizing the stability of the delivered Mesna in liquid form and for optimizing the delivery of said Mesna in liquid form to the target location at the desired concentration, volume and quality for surgical applications. In addition, the present invention aims at providing the user with a possibility to choose the concentration of the Mesna solution to be used. In addition, the invention aims at lowering the costs of the Mesna solution provided to the user.